Studies on the structure-functional relationship of various plant and bacteria toxins are being continued. The possible use of the native toxins and their modified products as potential agents in cancer chemotherapy is being investigated.The difference in binding mechanisms of toxins to various cells is being studied. Experiments are also being carried out on the mechanism by by which the toxic fragment (of the toxins) penetrates into cells, new approaches to cancer chemotherapy based on the nature of drug and hormone. Investigations on phosphorus metabolism in human tumors have been initiated. Enzymatic studies will continue on the pyridine nucleotide transhydrogenases as well as on the NADases from both bacteria and animal tissues.